Delimbing apparatus

ABSTRACT

A delimbing apparatus for the delimbing of trees, which can be connected to a moving vehicle via a boom system. The apparatus includes a frame part and a delimbing head. The frame part is provided with gripping elements, by which the frame part is fastened against the trunk of the tree at a desired height during delimbing work. The apparatus includes a delimbing head which is separate from the frame part and is provided with a gripping device for gripping the trunk of the tree. The delimbing head is moved by drive means along the tree trunk, and at least one delimbing cutter and a feed and control cable for transmitting operating power, connected between the delimbing head moving along the trunk of the tree and the frame part.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Finnish Application No. FI2001-1630 filed on Aug. 10, 2001 and International Application No.PCT/FI/02/00663 filed Aug. 12, 2002, the entire contents of which arehereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a delimbing apparatus.

2. Description of Background Art

Today, harvester heads are known that can be connected to a forestrymachine, by means of which trees are felled, delimbed and cut intopieces of desired length in one operation in the forest. This type ofharvester heads is thus only applicable for the felling of trees and thesubsequent handling of logs.

SUMMARY AND OBJECTS OF THE INVENTION

The object of the invention is to achieve a completely new type ofdelimbing apparatus that is applicable for pre-delimbing desired partsof living standing trees and, when necessary, also for thinning andfelling.

It is also an object of the invention to achieve an apparatus forproducing high-quality forest, by means of which trees can be delimbedwhile they are still alive, by removing dried-up and otherwise unviablebranches from the trees during their growth period, thus producing woodthat is excellently suited for use as raw material in wood industry.

The delimbing apparatus of the invention uses a separate delimbingdevice that, driven by a drive mechanism, is able to climb up the cleartrunk of a tree and cut off twigs and branches encountered. Also, whennecessary, delimbing apparatus can be used to fell the tree in givenlengths from above, or to cut it as a trunk from the base.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, the invention will be described in detail by the aidof an example with reference to the attached drawings, wherein

FIG. 1 presents a delimbing apparatus according to the invention, fittedon a forestry machine,

FIG. 2 presents the delimbing apparatus of the invention fitted onforestry machine, delimbing a standing tree,

FIG. 3 presents the delimbing head in side view,

FIG. 4 presents the frame part and the delimbing head with a rotatingupper cutter, ready to cut off the top of a tree,

FIG. 5 presents the frame part and the delimbing head with the rotatingupper cutter in a position for cutting heavy branches, and

FIG. 6 presents the frame part and the delimbing head with the rotatingupper cutter in rest position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1 and 2 present a delimbing apparatus used for the delimbing ofstanding trees T and designed to be mounted on a driving carrier 1,which may be a forestry machine moving on wheels or caterpillar chains,e.g. a forest tractor, or even an agricultural tractor, a gardentractor, a snow sledge or a corresponding forest vehicle. The delimbingapparatus is attached to a forestry machine via a boom system 2, whichis an A-shaped fully rotatable feeble-constructed mechanism providedwith additional extensions 14 reaching to a large distance.

The delimbing apparatus includes a frame part 3 pivotally connected tothe boom system. Connected to the frame part 3 is a multi-functionflexible hose system 10 for the transmission of operating power. Using adouble cable reel 9 provided in the frame part 3, the hose system isalso extended to the separate delimbing head 4 which climbs up the trunkof the tree T, so that the cable follows the trunk from the reel and itslength is automatically adjusted between the frame part 3 and thedelimbing head 4. The frame part 3 is provided with a cutter 5, by meansof which trees can also be felled/thinned, and jaws 15 that keep theframe part 3 immovable during the delimbing and possible cutting. Thejaws 15 are also applicable for removal of the trunk cut off, e.g. whenthe trunks are loaded onto a load carrier following the forestrymachine. The frame part 3 of the delimbing head is connected to the boomsystem 2 via a swivel joint 16 that allows the frame part to be turnedin a desired direction, which makes it easier to delimb trees standingclose by each other side by side and one behind the other without movingthe vehicle.

The delimbing head 4 engages the living standing tree T by means ofedged laminae 11 that are tightened around the trunk by means of anaccordion-type tightening device 12 (gripping device). In addition tothe edged laminae, the delimbing head 4 may also be provided with adevice for sawing large branches, such as a circular saw, which is usedwhen necessary. The delimbing head 4 moves up and down along the trunkby means of roller or wheel gears 13 having inclinable teeth (FIGS.3-6), which are rotated by drive motors and which, actuated by theaccordion-type tightening device 12, bite into the bark of the tree and,if necessary, into the trunk. The power source of the delimbing head mayconsist of a hydraulic, pneumatic or electric drive and an electroniccontrol unit or a combination of these, which receives its driving powervia the boom system 2 and the frame part 3 from the power engine bymeans of the continuous multi-function control and operating cablewhich, following the tree trunk, controls and operates the delimbinghead 4. Due to the inclinable motion gear structure, the delimbing head4 can turn horizontally, and it moves along the trunk, rotating about itif necessary, according to operator control.

The delimbing head 4 has a light construction, consisting of steel,aluminum or plastic components, and it requires no heavy boom system orsupporting structure. Using bayonet couplers 17, the delimbing head 4can be replaced to suit the forest type and the trunk diameter. Thedelimbing head 4 can be provided with a top cutter 8, which is used forimproving trees and for finishing felling areas. It can be turnedbetween vertical and horizontal positions, so it can also be used to cutlarge branches. The delimbing head 4 may be controlled using voice,light, radio or similar control, which can be programmed as required ineach case. A felling cutter 5 cuts the tree at its root in a desireddirection, and the trunk, being held by the jaws 15 of the frame part 4,can be moved to a desired place. The top cutter 8 of the delimbing head4 cuts off the top at a desired height in the case of improving thetree, or the case of felling the tree. The accordion-type tighteningdevice 12 is operated by hydraulic, pneumatic or electric power or by acombination of these. The top cutter 8 removes the unnecessary limbs andimproves the felling operation. In addition, the upper part of the framepart 3 has a conical, downward widening shape, so the branches fallingdown will not be caught on frame part 3, but instead will fall to thesides of the frame part 3. When the delimbing head 4 is coming down, thecone 3C of the frame part 3 guides it back onto its carrier.

The apparatus can be provided with location and measuring devices neededfor registering the growing and treated wood stock. In connection withthe treatment, the measuring devices perform an evaluation telling thetree, location, size, top height etc., which makes it easier for theforest owner to monitor the situation. Thus, each growing tree isindividualized and follow-up becomes easier. A log sheet or the likeproduced from this registration will later facilitate the determinationof wood quality, e.g. in connection with a sale.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are intendedto be included within the scope of the following claims.

1. The delimbing apparatus for the delimbing a tree, which can beconnected to a moving vehicle via a boom system, said apparatuscomprising: a frame part and a delimbing head disposed above the framepart, wherein the frame part is provided with gripping elements adaptedto fasten the frame part to a trunk of the tree at a desired heightduring delimbing work, and the delimbing head is separable from andmovable with respect to the frame part, and is provided with a grippingdevice adapted to grip the trunk of the tree, drive means for moving thedelimbing head along the tree trunk and at least one delimbing cutterattached to the delimbing head, and a feed and control cable fortransmitting operating power and control to the delimbing head, the feedand control cable extending between the frame part and the delimbinghead via a cable reel on the frame part, wherein the frame part isprovided with a felling cutter adapted to cut the tree at a root of thetree.
 2. The delimbing apparatus according to claim 1, wherein the atleast one delimbing cutter is adapted to cut branches and the trunk. 3.The delimbing apparatus according to claim 1, wherein the drive meansincludes wheels or rollers rotated by a drive motor and controlled by acontrol unit.
 4. The delimbing apparatus according to claim 1, whereindrive means is inclinable, so that the at least one delimbing cutter ismovable in a desired direction along the trunk of the tree.
 5. Thedelimbing apparatus according to claim 1, wherein the delimbing cutteris fitted in conjunction with the gripping device, wherein the grippingdevice is a controllable accordion tightening device having controllableelements that are capable of being tightened around the trunk of thetree.
 6. The delimbing apparatus according to claim 1, wherein the framepart is adapted to widen conically downward, allowing the delimbing headto be parked in an initial position with respect to the frame part. 7.The delimbing apparatus according to claim 1, wherein the frame part isconnected to the boom system via a swivel joint, wherein the boom systemis adapted to allow the frame part to be turned in a desired direction,in order to enable the apparatus to delimb trees standing adjacent toeach other side by side and one behind another, without moving thevehicle.
 8. The delimbing apparatus according to claim 1, wherein theboom system connects the frame part to the vehicle and is substantiallyA-shaped.
 9. The delimbing apparatus according to claim 1, wherein theboom system is disposed between the frame part and the vehicle, and isfitted to the vehicle so that the boom system is fully rotatable withrespect to the vehicle.
 10. The delimbing apparatus according to claim1, wherein the cable between the delimbing head and the frame partfollows the trunk of the tree and moves parallel to the trunk of thetree.
 11. The delimbing apparatus according to claim 1, wherein thedelimbing head is detachably coupled to the frame part by bayonetcouplers, so that the delimbing head is replaceable to suit conditionsin different forests and trees with different trunk diameters.
 12. Thedelimbing apparatus according to claim 1, wherein the at least onedelimbing cutter is a top cutter fitted to the delimbing head, the topcutter being pivotable between vertical and horizontal positions, sothat, in addition to cutting the tree, the top cutter can be used forcutting branches.
 13. The delimbing apparatus according to claim 5,wherein the controllable accordion tightening device includes edgedlaminae that are arranged in a curved shape for bending around the trunkof the tree.
 14. The delimbing apparatus according to claim 1, whereinthe felling cutter is provided on a lower portion of the frame partadjacent to the cable reel.
 15. The delimbing apparatus according toclaim 1, wherein the feed and control cable follows the trunk of thetree from the cable reel, and a length of the cable is automaticallyadjusted between the frame part and the delimbing head, thereby avoidingswinging of the cable.